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AR# 20959

6.1.03 NDGBuild -- Offset constraints with EXCEPT cause ERROR:XdmHelpers:667.


Keywords: Offset, EXCEPT, XdmHelpers, 667

Urgency: Standard

General Description:
When I use an EXCEPT statement in the constraints file to exclude non-synchronous elements, the following errors are incorrectly shown in NGDBuild.

ERROR:XdmHelpers:667 - OFFSET specification "TIMEGRP xxx_grp OFFSET=IN
10000.000000 pS BEFORE yyy TIMEGRP zzz" references a register group
(zzz), which contains one or more pad elements. The optional register
group must contain only synchronous elements.

NET "xxx" TNM = "xxx_grp";
TIMEGRP "" = "xxx_grp" EXCEPT "clk";
TIMEGRP "xxx_grp" OFFSET = IN 10 ns BEFORE "yyy" TIMEGRP "zzz";


In some cases the EXCEPT is not correctly processed. This has been fixed in the 7.1i software.

You can work around this in the 6.xi software by specifying the groups without using the EXCEPT keyword.

One way of doing it would be to define the group without the synchronous element.

AR# 20959
Date Created 03/11/2005
Last Updated 02/21/2007
Status Archive
Type General Article